Jean Piaget described four major stages of development, each stage with sub-stages. Piaget’s stages of cognitive development extend from infancy to adulthood.
Piaget’s stages of cognitive development
1. The sensorimotor stage ( birth – 2 years)
The first stage is based on the idea that the infant has sensory experiences (a baby can see, hear, smell, taste, feel) and the baby can move the parts of his body (motor movements). This is why Piaget called the first stage “the sensorimotor stage”.
During this stage, the child begins to notice the differences between him and the objects from his environment, to appreciate time and space.
The sensorimotor stage has 6 sub-stages.
1.1. Simple Reflexes (birth – 1 month)
During this stage children have no concept of the object, they can return their head and look after a sound source but they will never show any reaction to a hidden object. The child understands the environment through inborn reflexes (such as looking).
1.2. Primary Circular Reactions (1– 4 months)
During the second sub-stage, children begin to follow the movement of objects. If an object disappears, the child will look in the same place. If the object does not reappear soon, the child will lose interest in it. The child expects the object to reappear but he does not look for it. Piaget called this phenomenon “passive waiting.”
1.3. Secondary Circular Reactions (4 – 8 months)
The child is now able to take and hold objects in his hand, to look for objects that are visible or partially visible.
1.4. Coordination of Reactions (8-12 months)
During the fourth sub-stage, the child investigates the properties of an object. If an object is hidden, the child will look for it. The child can’t see the hidden object but he knows that it still exists, hidden somewhere.
1.5. Tertiary Circular Reactions (12-18 months)
At this stage, the child is able to look for the hidden objects in the last place he saw the hidden object.
1.6. Early Representational Thought (18-24 months)
According to Piaget’s theory, during this stage, the child begins to think, to deduce the movements of a hidden object.
2. Preoperational stage (2 – 7 years)
During the preoperational stage, the language skills are developed as well as the ability to make symbolic representations using objects. The child does not develop the ability to perceive the conservation of mass, volume, number, or height.
Let’s take an example:
There are two identical glasses on table, with the same shape and volume. We put the same amount of water in both glasses. The child is able to say that the two glasses are equal. Than we take another glass, with the same volume but with a different shape. We put the same amount of water in this glass. The child will say that one glass has more or less water. He is not able to understand that there is the same amount of water in all glasses.
3. The concrete Operational Stage ( 7 – 12 years)
During this stage, children develop the ability to perceive the feelings and attitudes of people around them. They are now able to better understand the cause-effect relation. The symbolical thinking is improved during the concrete operational stage.
At this age, children believe that people around them can see the world and understand it the same way they do.
4. The formal operational stage ( 12 years – adulthood)
The last stage of development described by Jean Piaget begins at puberty and lasts into adulthood. During this stage, people develop the ability to think about abstract concepts. Others skills developed during the last stage of cognitive development are logical thought, deductive reasoning, and systematic planning.
Mitchell, P., Ziegler, F. (2007). Fundamentals of Human Development. Psychology Press, Hove
Harris, M., Butterworth, G. (2002). Developmental Psychology – A student’s Handbook. Psychology Press, Hove